Add new plugin for github version of gitlab_merge_requests.js

[SimeonC]

My company moved from gitlab to github so I re-wrote my plugin to work with github to keep the same workflow.

[SimeonC]

@matryer Have updated the file name to include the default timeout as in the docs (missed this earlier). Is there anything else blocking this from being merged?

[viperfx]

@SimeonC how do you currently set this up? I get an error

import fs from "fs";
^^^^^^

SyntaxError: Cannot use import statement outside a module

[SimeonC]

Hmmm, it should just work due to the mjs file extension. What version of node.js are you running?